See also:

5 Series Gran Turismo
For 2010, BMW added a hatchback version of its rear-wheel-drive 5 Series,
dubbed the 5 Series Gran Turismo, starting with a 550i "GT" powered by the same
400-hp, twin-turbo V-8 as the 55 ...

Tone control
You can alter various tone settings, e.g. treble and bass or the speed-dependent
volume increase.
The tone settings are applied to all audio sources.
The settings are stored for the remote control ...